What exactly does this mean Radcliffe, 22, needs to do? "I think it means I have to be able to cook for myself better than I can at the moment," he explained. "And it means that I can't leave the house in a state the way I do."

While the actor "didn't promise her anything," he joked, "I have made it my mission to improve myself. There's certainly progress to be made."

The star and Coker, a production assistant, met on the "Harry Potter" set over a year ago. "She's busy, I'm busy, but we're making it work and it's good," he told the Daily Mail. "She's helped me grow up, and I love her very much."